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Original commit message from CVS: * gst/gstbus.c: use HAVE_UNISTD_H * win32/common/config.h: update config * win32/vs6/grammar.dsp: * win32/vs6/libgstelements.dsp: * win32/vs6/libgstreamer.dsp: update vs6 files
951 lines
24 KiB
C
951 lines
24 KiB
C
/* GStreamer
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* Copyright (C) 2004 Wim Taymans <wim@fluendo.com>
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*
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* gstbus.c: GstBus subsystem
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 02111-1307, USA.
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*/
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/**
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* SECTION:gstbus
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* @short_description: Asynchronous message bus subsystem
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* @see_also: #GstMessage, #GstElement
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*
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* The #GstBus is an object responsible for delivering #GstMessages in
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* a first-in first-out way from the streaming threads to the application.
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*
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* Since the application typically only wants to deal with delivery of these
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* messages from one thread, the GstBus will marshall the messages between
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* different threads. This is important since the actual streaming of media
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* is done in another thread than the application.
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*
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* The GstBus provides support for #GSource based notifications. This makes it
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* possible to handle the delivery in the glib mainloop.
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*
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* The #GSource callback function gst_bus_async_signal_func() can be used to
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* convert all bus messages into signal emissions.
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*
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* A message is posted on the bus with the gst_bus_post() method. With the
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* gst_bus_peek() and _pop() methods one can look at or retrieve a previously
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* posted message.
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*
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* The bus can be polled with the gst_bus_poll() method. This methods blocks
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* up to the specified timeout value until one of the specified messages types
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* is posted on the bus. The application can then _pop() the messages from the
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* bus to handle them.
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* Alternatively the application can register an asynchronous bus function using
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* gst_bus_add_watch_full() or gst_bus_add_watch(). This function will receive
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* messages a short while after they have been posted.
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*
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* It is also possible to get messages from the bus without any thread
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* marshalling with the gst_bus_set_sync_handler() method. This makes it
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* possible to react to a message in the same thread that posted the
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* message on the bus. This should only be used if the application is able
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* to deal with messages from different threads.
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*
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* Every #GstPipeline has one bus.
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*
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* Note that a #GstPipeline will set its bus into flushing state when changing from
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* READY to NULL state.
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*/
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#include <errno.h>
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#ifdef HAVE_UNISTD_H
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# include <unistd.h>
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#endif
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#include <sys/types.h>
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#include "gst_private.h"
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#include "gstinfo.h"
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#include "gstbus.h"
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#define GST_CAT_DEFAULT GST_CAT_BUS
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/* bus signals */
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enum
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{
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SYNC_MESSAGE,
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ASYNC_MESSAGE,
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/* add more above */
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LAST_SIGNAL
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};
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static void gst_bus_class_init (GstBusClass * klass);
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static void gst_bus_init (GstBus * bus);
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static void gst_bus_dispose (GObject * object);
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static void gst_bus_set_property (GObject * object, guint prop_id,
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const GValue * value, GParamSpec * pspec);
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static void gst_bus_get_property (GObject * object, guint prop_id,
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GValue * value, GParamSpec * pspec);
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static GstObjectClass *parent_class = NULL;
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static guint gst_bus_signals[LAST_SIGNAL] = { 0 };
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GType
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gst_bus_get_type (void)
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{
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static GType bus_type = 0;
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if (!bus_type) {
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static const GTypeInfo bus_info = {
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sizeof (GstBusClass),
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NULL,
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NULL,
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(GClassInitFunc) gst_bus_class_init,
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NULL,
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NULL,
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sizeof (GstBus),
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0,
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(GInstanceInitFunc) gst_bus_init,
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NULL
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};
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bus_type = g_type_register_static (GST_TYPE_OBJECT, "GstBus", &bus_info, 0);
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}
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return bus_type;
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}
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/* fixme: do something about this */
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static void
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marshal_VOID__MINIOBJECT (GClosure * closure, GValue * return_value,
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guint n_param_values, const GValue * param_values, gpointer invocation_hint,
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gpointer marshal_data)
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{
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typedef void (*marshalfunc_VOID__MINIOBJECT) (gpointer obj, gpointer arg1,
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gpointer data2);
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register marshalfunc_VOID__MINIOBJECT callback;
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register GCClosure *cc = (GCClosure *) closure;
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register gpointer data1, data2;
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g_return_if_fail (n_param_values == 2);
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if (G_CCLOSURE_SWAP_DATA (closure)) {
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data1 = closure->data;
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data2 = g_value_peek_pointer (param_values + 0);
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} else {
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data1 = g_value_peek_pointer (param_values + 0);
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data2 = closure->data;
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}
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callback =
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(marshalfunc_VOID__MINIOBJECT) (marshal_data ? marshal_data : cc->
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callback);
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callback (data1, gst_value_get_mini_object (param_values + 1), data2);
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}
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static void
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gst_bus_class_init (GstBusClass * klass)
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{
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GObjectClass *gobject_class;
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GstObjectClass *gstobject_class;
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gobject_class = (GObjectClass *) klass;
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gstobject_class = (GstObjectClass *) klass;
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parent_class = g_type_class_peek_parent (klass);
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if (!g_thread_supported ())
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g_thread_init (NULL);
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gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_bus_dispose);
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gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_bus_set_property);
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gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_bus_get_property);
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/**
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* GstBus::sync-message:
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* @bus: the object which received the signal
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* @message: the message that has been posted synchronously
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*
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* A message has been posted on the bus. This signal is emited from the
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* thread that posted the message so one has to be carefull with locking.
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*/
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gst_bus_signals[SYNC_MESSAGE] =
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g_signal_new ("sync-message", G_TYPE_FROM_CLASS (klass),
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G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
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G_STRUCT_OFFSET (GstBusClass, sync_message), NULL, NULL,
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marshal_VOID__MINIOBJECT, G_TYPE_NONE, 1, GST_TYPE_MESSAGE);
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/**
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* GstBus::message:
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* @bus: the object which received the signal
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* @message: the message that has been posted asynchronously
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*
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* A message has been posted on the bus. This signal is emited from a
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* GSource added to the mainloop.
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*/
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gst_bus_signals[ASYNC_MESSAGE] =
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g_signal_new ("message", G_TYPE_FROM_CLASS (klass),
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G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
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G_STRUCT_OFFSET (GstBusClass, message), NULL, NULL,
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marshal_VOID__MINIOBJECT, G_TYPE_NONE, 1, GST_TYPE_MESSAGE);
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}
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static void
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gst_bus_init (GstBus * bus)
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{
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bus->queue = g_queue_new ();
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bus->queue_lock = g_mutex_new ();
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GST_DEBUG_OBJECT (bus, "created");
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return;
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}
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static void
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gst_bus_dispose (GObject * object)
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{
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GstBus *bus;
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bus = GST_BUS (object);
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if (bus->queue) {
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GstMessage *message;
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g_mutex_lock (bus->queue_lock);
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do {
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message = g_queue_pop_head (bus->queue);
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if (message)
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gst_message_unref (message);
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} while (message != NULL);
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g_queue_free (bus->queue);
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bus->queue = NULL;
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g_mutex_unlock (bus->queue_lock);
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g_mutex_free (bus->queue_lock);
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bus->queue_lock = NULL;
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}
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G_OBJECT_CLASS (parent_class)->dispose (object);
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}
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static void
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gst_bus_set_property (GObject * object, guint prop_id,
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const GValue * value, GParamSpec * pspec)
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{
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GstBus *bus;
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bus = GST_BUS (object);
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switch (prop_id) {
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default:
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G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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break;
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}
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}
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static void
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gst_bus_get_property (GObject * object, guint prop_id,
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GValue * value, GParamSpec * pspec)
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{
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GstBus *bus;
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bus = GST_BUS (object);
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switch (prop_id) {
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default:
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G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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break;
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}
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}
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/**
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* gst_bus_new:
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*
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* Creates a new #GstBuus instance.
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*
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* Returns: a new #GstBus instance
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*/
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GstBus *
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gst_bus_new (void)
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{
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GstBus *result;
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result = g_object_new (gst_bus_get_type (), NULL);
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return result;
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}
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/**
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* gst_bus_post:
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* @bus: a #GstBus to post on
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* @message: The #GstMessage to post
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*
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* Post a message on the given bus. Ownership of the message
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* is taken by the bus.
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*
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* Returns: TRUE if the message could be posted.
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*
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* MT safe.
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*/
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gboolean
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gst_bus_post (GstBus * bus, GstMessage * message)
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{
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GstBusSyncReply reply = GST_BUS_PASS;
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GstBusSyncHandler handler;
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gpointer handler_data;
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g_return_val_if_fail (GST_IS_BUS (bus), FALSE);
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g_return_val_if_fail (GST_IS_MESSAGE (message), FALSE);
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GST_DEBUG_OBJECT (bus, "[msg %p] posting on bus, type %s",
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message, gst_message_type_get_name (GST_MESSAGE_TYPE (message)));
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GST_LOCK (bus);
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/* check if the bus is flushing */
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if (GST_OBJECT_FLAG_IS_SET (bus, GST_BUS_FLUSHING))
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goto is_flushing;
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handler = bus->sync_handler;
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handler_data = bus->sync_handler_data;
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GST_UNLOCK (bus);
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/* first call the sync handler if it is installed */
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if (handler)
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reply = handler (bus, message, handler_data);
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/* now see what we should do with the message */
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switch (reply) {
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case GST_BUS_DROP:
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/* drop the message */
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GST_DEBUG_OBJECT (bus, "[msg %p] dropped", message);
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break;
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case GST_BUS_PASS:
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/* pass the message to the async queue, refcount passed in the queue */
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GST_DEBUG_OBJECT (bus, "[msg %p] pushing on async queue", message);
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g_mutex_lock (bus->queue_lock);
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g_queue_push_tail (bus->queue, message);
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g_mutex_unlock (bus->queue_lock);
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GST_DEBUG_OBJECT (bus, "[msg %p] pushed on async queue", message);
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/* FIXME cannot assume the source is only in the default context */
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g_main_context_wakeup (NULL);
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break;
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case GST_BUS_ASYNC:
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{
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/* async delivery, we need a mutex and a cond to block
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* on */
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GMutex *lock = g_mutex_new ();
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GCond *cond = g_cond_new ();
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GST_MESSAGE_COND (message) = cond;
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GST_MESSAGE_GET_LOCK (message) = lock;
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GST_DEBUG_OBJECT (bus, "[msg %p] waiting for async delivery", message);
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/* now we lock the message mutex, send the message to the async
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* queue. When the message is handled by the app and destroyed,
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* the cond will be signalled and we can continue */
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g_mutex_lock (lock);
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g_mutex_lock (bus->queue_lock);
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g_queue_push_tail (bus->queue, message);
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g_mutex_unlock (bus->queue_lock);
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/* FIXME cannot assume the source is only in the default context */
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g_main_context_wakeup (NULL);
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/* now block till the message is freed */
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g_cond_wait (cond, lock);
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g_mutex_unlock (lock);
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GST_DEBUG_OBJECT (bus, "[msg %p] delivered asynchronously", message);
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g_mutex_free (lock);
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g_cond_free (cond);
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break;
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}
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default:
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g_warning ("invalid return from bus sync handler");
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break;
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}
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return TRUE;
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/* ERRORS */
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is_flushing:
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{
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GST_DEBUG_OBJECT (bus, "bus is flushing");
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gst_message_unref (message);
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GST_UNLOCK (bus);
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return FALSE;
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}
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}
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/**
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* gst_bus_have_pending:
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* @bus: a #GstBus to check
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*
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* Check if there are pending messages on the bus that
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* should be handled.
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*
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* Returns: TRUE if there are messages on the bus to be handled.
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*
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* MT safe.
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*/
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gboolean
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gst_bus_have_pending (GstBus * bus)
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{
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gboolean result;
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g_return_val_if_fail (GST_IS_BUS (bus), FALSE);
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g_mutex_lock (bus->queue_lock);
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/* see if there is a message on the bus */
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result = !g_queue_is_empty (bus->queue);
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g_mutex_unlock (bus->queue_lock);
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return result;
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}
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/**
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* gst_bus_set_flushing:
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* @bus: a #GstBus
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* @flushing: whether or not to flush the bus
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*
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* If @flushing, flush out and unref any messages queued in the bus. Releases
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* references to the message origin objects. Will flush future messages until
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* gst_bus_set_flushing() sets @flushing to #FALSE.
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*
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* MT safe.
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*/
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void
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gst_bus_set_flushing (GstBus * bus, gboolean flushing)
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{
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GstMessage *message;
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GST_LOCK (bus);
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if (flushing) {
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GST_OBJECT_FLAG_SET (bus, GST_BUS_FLUSHING);
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GST_DEBUG_OBJECT (bus, "set bus flushing");
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while ((message = gst_bus_pop (bus)))
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gst_message_unref (message);
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} else {
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GST_DEBUG_OBJECT (bus, "unset bus flushing");
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GST_OBJECT_FLAG_UNSET (bus, GST_BUS_FLUSHING);
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}
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GST_UNLOCK (bus);
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}
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/**
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* gst_bus_pop:
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* @bus: a #GstBus to pop
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*
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* Get a message from the bus.
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*
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* Returns: The #GstMessage that is on the bus, or NULL if the bus is empty.
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*
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* MT safe.
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*/
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GstMessage *
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gst_bus_pop (GstBus * bus)
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{
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GstMessage *message;
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g_return_val_if_fail (GST_IS_BUS (bus), NULL);
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g_mutex_lock (bus->queue_lock);
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message = g_queue_pop_head (bus->queue);
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if (message)
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GST_DEBUG_OBJECT (bus, "pop from bus, have %d messages, got message %p, %s",
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g_queue_get_length (bus->queue) + 1, message,
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gst_message_type_get_name (GST_MESSAGE_TYPE (message)));
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else
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GST_DEBUG_OBJECT (bus, "pop from bus, no messages");
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g_mutex_unlock (bus->queue_lock);
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return message;
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}
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/**
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* gst_bus_peek:
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* @bus: a #GstBus
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*
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* Peek the message on the top of the bus' queue. The message will remain
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* on the bus' message queue. A reference is returned, and needs to be unreffed
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* by the caller.
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*
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* Returns: The #GstMessage that is on the bus, or NULL if the bus is empty.
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*
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* MT safe.
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*/
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GstMessage *
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gst_bus_peek (GstBus * bus)
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{
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GstMessage *message;
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g_return_val_if_fail (GST_IS_BUS (bus), NULL);
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g_mutex_lock (bus->queue_lock);
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message = g_queue_peek_head (bus->queue);
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if (message)
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gst_message_ref (message);
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g_mutex_unlock (bus->queue_lock);
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GST_DEBUG_OBJECT (bus, "peek on bus, got message %p", message);
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return message;
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}
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/**
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* gst_bus_set_sync_handler:
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* @bus: a #GstBus to install the handler on
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* @func: The handler function to install
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* @data: User data that will be sent to the handler function.
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*
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* Sets the synchronous handler on the bus. The function will be called
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* every time a new message is posted on the bus. Note that the function
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* will be called in the same thread context as the posting object. This
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* function is usually only called by the creator of the bus. Applications
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* should handle messages asynchronously using the gst_bus watch and poll
|
|
* functions.
|
|
*/
|
|
void
|
|
gst_bus_set_sync_handler (GstBus * bus, GstBusSyncHandler func, gpointer data)
|
|
{
|
|
g_return_if_fail (GST_IS_BUS (bus));
|
|
|
|
GST_LOCK (bus);
|
|
|
|
/* Assert if the user attempts to replace an existing sync_handler,
|
|
* other than to clear it */
|
|
g_assert (func == NULL || bus->sync_handler == NULL);
|
|
|
|
bus->sync_handler = func;
|
|
bus->sync_handler_data = data;
|
|
GST_UNLOCK (bus);
|
|
}
|
|
|
|
/* GSource for the bus
|
|
*/
|
|
typedef struct
|
|
{
|
|
GSource source;
|
|
GstBus *bus;
|
|
} GstBusSource;
|
|
|
|
static gboolean
|
|
gst_bus_source_prepare (GSource * source, gint * timeout)
|
|
{
|
|
GstBusSource *bsrc = (GstBusSource *) source;
|
|
|
|
*timeout = -1;
|
|
return gst_bus_have_pending (bsrc->bus);
|
|
}
|
|
|
|
static gboolean
|
|
gst_bus_source_check (GSource * source)
|
|
{
|
|
GstBusSource *bsrc = (GstBusSource *) source;
|
|
|
|
return gst_bus_have_pending (bsrc->bus);
|
|
}
|
|
|
|
static gboolean
|
|
gst_bus_source_dispatch (GSource * source, GSourceFunc callback,
|
|
gpointer user_data)
|
|
{
|
|
GstBusFunc handler = (GstBusFunc) callback;
|
|
GstBusSource *bsource = (GstBusSource *) source;
|
|
GstMessage *message;
|
|
gboolean keep;
|
|
GstBus *bus;
|
|
|
|
g_return_val_if_fail (bsource != NULL, FALSE);
|
|
|
|
bus = bsource->bus;
|
|
|
|
g_return_val_if_fail (GST_IS_BUS (bus), FALSE);
|
|
|
|
message = gst_bus_pop (bus);
|
|
g_return_val_if_fail (message != NULL, FALSE);
|
|
|
|
if (!handler)
|
|
goto no_handler;
|
|
|
|
GST_DEBUG_OBJECT (bus, "source %p calling dispatch with %p", source, message);
|
|
|
|
keep = handler (bus, message, user_data);
|
|
gst_message_unref (message);
|
|
|
|
GST_DEBUG_OBJECT (bus, "source %p handler returns %d", source, keep);
|
|
|
|
return keep;
|
|
|
|
no_handler:
|
|
{
|
|
g_warning ("GstBus watch dispatched without callback\n"
|
|
"You must call g_source_connect().");
|
|
gst_message_unref (message);
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
static void
|
|
gst_bus_source_finalize (GSource * source)
|
|
{
|
|
GstBusSource *bsource = (GstBusSource *) source;
|
|
|
|
gst_object_unref (bsource->bus);
|
|
bsource->bus = NULL;
|
|
}
|
|
|
|
static GSourceFuncs gst_bus_source_funcs = {
|
|
gst_bus_source_prepare,
|
|
gst_bus_source_check,
|
|
gst_bus_source_dispatch,
|
|
gst_bus_source_finalize
|
|
};
|
|
|
|
/**
|
|
* gst_bus_create_watch:
|
|
* @bus: a #GstBus to create the watch for
|
|
*
|
|
* Create watch for this bus. The GSource will be dispatched whenever
|
|
* a message is on the bus. After the GSource is dispatched, the
|
|
* message is popped off the bus and unreffed.
|
|
*
|
|
* Returns: A #GSource that can be added to a mainloop.
|
|
*/
|
|
GSource *
|
|
gst_bus_create_watch (GstBus * bus)
|
|
{
|
|
GstBusSource *source;
|
|
|
|
g_return_val_if_fail (GST_IS_BUS (bus), NULL);
|
|
|
|
source = (GstBusSource *) g_source_new (&gst_bus_source_funcs,
|
|
sizeof (GstBusSource));
|
|
gst_object_ref (bus);
|
|
source->bus = bus;
|
|
|
|
return (GSource *) source;
|
|
}
|
|
|
|
/**
|
|
* gst_bus_add_watch_full:
|
|
* @bus: a #GstBus to create the watch for.
|
|
* @priority: The priority of the watch.
|
|
* @func: A function to call when a message is received.
|
|
* @user_data: user data passed to @func.
|
|
* @notify: the function to call when the source is removed.
|
|
*
|
|
* Adds a bus watch to the default main context with the given priority.
|
|
* If the func returns FALSE, the source will be removed.
|
|
*
|
|
* When the func is called, the message belongs to the caller; if you want to
|
|
* keep a copy of it, call gst_message_ref() before leaving the func.
|
|
*
|
|
* The watch can be removed using #g_source_remove().
|
|
*
|
|
* Returns: The event source id.
|
|
*
|
|
* MT safe.
|
|
*/
|
|
guint
|
|
gst_bus_add_watch_full (GstBus * bus, gint priority,
|
|
GstBusFunc func, gpointer user_data, GDestroyNotify notify)
|
|
{
|
|
guint id;
|
|
GSource *source;
|
|
|
|
g_return_val_if_fail (GST_IS_BUS (bus), 0);
|
|
|
|
source = gst_bus_create_watch (bus);
|
|
|
|
if (priority != G_PRIORITY_DEFAULT)
|
|
g_source_set_priority (source, priority);
|
|
|
|
g_source_set_callback (source, (GSourceFunc) func, user_data, notify);
|
|
|
|
id = g_source_attach (source, NULL);
|
|
g_source_unref (source);
|
|
|
|
GST_DEBUG_OBJECT (bus, "New source %p", source);
|
|
return id;
|
|
}
|
|
|
|
/**
|
|
* gst_bus_add_watch:
|
|
* @bus: a #GstBus to create the watch for
|
|
* @func: A function to call when a message is received.
|
|
* @user_data: user data passed to @func.
|
|
*
|
|
* Adds a bus watch to the default main context with the default priority.
|
|
*
|
|
* The watch can be removed using #g_source_remove().
|
|
*
|
|
* Returns: The event source id.
|
|
*
|
|
* MT safe.
|
|
*/
|
|
guint
|
|
gst_bus_add_watch (GstBus * bus, GstBusFunc func, gpointer user_data)
|
|
{
|
|
return gst_bus_add_watch_full (bus, G_PRIORITY_DEFAULT, func,
|
|
user_data, NULL);
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
GMainLoop *loop;
|
|
guint timeout_id;
|
|
gboolean source_running;
|
|
GstMessageType events;
|
|
GstMessage *message;
|
|
} GstBusPollData;
|
|
|
|
static gboolean
|
|
poll_func (GstBus * bus, GstMessage * message, GstBusPollData * poll_data)
|
|
{
|
|
if (!g_main_loop_is_running (poll_data->loop)) {
|
|
GST_DEBUG ("mainloop %p not running", poll_data->loop);
|
|
return TRUE;
|
|
}
|
|
|
|
if (GST_MESSAGE_TYPE (message) & poll_data->events) {
|
|
g_return_val_if_fail (poll_data->message == NULL, FALSE);
|
|
/* keep ref to message */
|
|
poll_data->message = gst_message_ref (message);
|
|
GST_DEBUG ("mainloop %p quit", poll_data->loop);
|
|
g_main_loop_quit (poll_data->loop);
|
|
}
|
|
|
|
/* we always keep the source alive so that we don't accidentialy
|
|
* free the poll_data */
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
poll_timeout (GstBusPollData * poll_data)
|
|
{
|
|
GST_DEBUG ("mainloop %p quit", poll_data->loop);
|
|
g_main_loop_quit (poll_data->loop);
|
|
|
|
/* we don't remove the GSource as this would free our poll_data,
|
|
* which we still need */
|
|
return TRUE;
|
|
}
|
|
|
|
static void
|
|
poll_destroy (GstBusPollData * poll_data)
|
|
{
|
|
poll_data->source_running = FALSE;
|
|
if (!poll_data->timeout_id) {
|
|
g_main_loop_unref (poll_data->loop);
|
|
g_free (poll_data);
|
|
}
|
|
}
|
|
|
|
static void
|
|
poll_destroy_timeout (GstBusPollData * poll_data)
|
|
{
|
|
poll_data->timeout_id = 0;
|
|
if (!poll_data->source_running) {
|
|
g_main_loop_unref (poll_data->loop);
|
|
g_free (poll_data);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_bus_poll:
|
|
* @bus: a #GstBus
|
|
* @events: a mask of #GstMessageType, representing the set of message types to
|
|
* poll for.
|
|
* @timeout: the poll timeout, as a #GstClockTimeDiff, or -1 to poll indefinitely.
|
|
*
|
|
* Poll the bus for events. Will block while waiting for events to come. You can
|
|
* specify a maximum time to poll with the @timeout parameter. If @timeout is
|
|
* negative, this function will block indefinitely.
|
|
*
|
|
* All messages not in @events will be popped off the bus and will be ignored.
|
|
*
|
|
* This function will enter the default mainloop while polling.
|
|
*
|
|
* Returns: The message that was received, or NULL if the poll timed out.
|
|
* The message is taken from the bus and needs to be unreffed after usage.
|
|
*/
|
|
GstMessage *
|
|
gst_bus_poll (GstBus * bus, GstMessageType events, GstClockTimeDiff timeout)
|
|
{
|
|
GstBusPollData *poll_data;
|
|
GstMessage *ret;
|
|
guint id;
|
|
|
|
poll_data = g_new0 (GstBusPollData, 1);
|
|
poll_data->source_running = TRUE;
|
|
poll_data->loop = g_main_loop_new (NULL, FALSE);
|
|
poll_data->events = events;
|
|
poll_data->message = NULL;
|
|
|
|
if (timeout >= 0)
|
|
poll_data->timeout_id = g_timeout_add_full (G_PRIORITY_DEFAULT_IDLE,
|
|
timeout / GST_MSECOND, (GSourceFunc) poll_timeout, poll_data,
|
|
(GDestroyNotify) poll_destroy_timeout);
|
|
else
|
|
poll_data->timeout_id = 0;
|
|
|
|
id = gst_bus_add_watch_full (bus, G_PRIORITY_DEFAULT,
|
|
(GstBusFunc) poll_func, poll_data, (GDestroyNotify) poll_destroy);
|
|
|
|
GST_DEBUG ("running mainloop %p", poll_data->loop);
|
|
g_main_loop_run (poll_data->loop);
|
|
GST_DEBUG ("mainloop stopped %p", poll_data->loop);
|
|
/* holds a ref */
|
|
ret = poll_data->message;
|
|
|
|
if (poll_data->timeout_id)
|
|
g_source_remove (poll_data->timeout_id);
|
|
|
|
/* poll_data may get destroyed at any time now */
|
|
g_source_remove (id);
|
|
|
|
GST_DEBUG_OBJECT (bus, "finished poll with message %p", ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gst_bus_async_signal_func:
|
|
* @bus: a #GstBus
|
|
* @message: the message received
|
|
* @data: user data
|
|
*
|
|
* A helper GstBusFunc that can be used to convert all asynchronous messages
|
|
* into signals.
|
|
*
|
|
* Returns: TRUE
|
|
*/
|
|
gboolean
|
|
gst_bus_async_signal_func (GstBus * bus, GstMessage * message, gpointer data)
|
|
{
|
|
GQuark detail = 0;
|
|
|
|
g_return_val_if_fail (GST_IS_BUS (bus), TRUE);
|
|
g_return_val_if_fail (message != NULL, TRUE);
|
|
|
|
detail = gst_message_type_to_quark (GST_MESSAGE_TYPE (message));
|
|
|
|
g_signal_emit (bus, gst_bus_signals[ASYNC_MESSAGE], detail, message);
|
|
|
|
/* we never remove this source based on signal emission return values */
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
* gst_bus_sync_signal_handler:
|
|
* @bus: a #GstBus
|
|
* @message: the message received
|
|
* @data: user data
|
|
*
|
|
* A helper GstBusSyncHandler that can be used to convert all synchronous
|
|
* messages into signals.
|
|
*
|
|
* Returns: GST_BUS_PASS
|
|
*/
|
|
GstBusSyncReply
|
|
gst_bus_sync_signal_handler (GstBus * bus, GstMessage * message, gpointer data)
|
|
{
|
|
GQuark detail = 0;
|
|
|
|
g_return_val_if_fail (GST_IS_BUS (bus), GST_BUS_DROP);
|
|
g_return_val_if_fail (message != NULL, GST_BUS_DROP);
|
|
|
|
detail = gst_message_type_to_quark (GST_MESSAGE_TYPE (message));
|
|
|
|
g_signal_emit (bus, gst_bus_signals[SYNC_MESSAGE], detail, message);
|
|
|
|
return GST_BUS_PASS;
|
|
}
|
|
|
|
/**
|
|
* gst_bus_add_signal_watch:
|
|
* @bus: a #GstBus on which you want to recieve the "message" signal
|
|
*
|
|
* Adds a bus signal watch to the default main context with the default priority.
|
|
* After calling this statement, the bus will emit the message signal for each
|
|
* message posted on the bus.
|
|
*
|
|
* This function may be called multiple times. To clean up, the caller is
|
|
* responsible for calling gst_bus_remove_signal_watch() as many times as this
|
|
* function is called.
|
|
*
|
|
* MT safe.
|
|
*/
|
|
void
|
|
gst_bus_add_signal_watch (GstBus * bus)
|
|
{
|
|
g_return_if_fail (GST_IS_BUS (bus));
|
|
|
|
/* I know the callees don't take this lock, so go ahead and abuse it */
|
|
GST_LOCK (bus);
|
|
|
|
if (bus->num_signal_watchers > 0)
|
|
goto done;
|
|
|
|
g_assert (bus->signal_watch_id == 0);
|
|
|
|
bus->signal_watch_id =
|
|
gst_bus_add_watch (bus, gst_bus_async_signal_func, NULL);
|
|
|
|
done:
|
|
|
|
bus->num_signal_watchers++;
|
|
|
|
GST_UNLOCK (bus);
|
|
}
|
|
|
|
/**
|
|
* gst_bus_remove_signal_watch:
|
|
* @bus: a #GstBus you previously added a signal watch to
|
|
*
|
|
* Removes a signal watch previously added with gst_bus_add_signal_watch().
|
|
*
|
|
* MT safe.
|
|
*/
|
|
void
|
|
gst_bus_remove_signal_watch (GstBus * bus)
|
|
{
|
|
g_return_if_fail (GST_IS_BUS (bus));
|
|
|
|
/* I know the callees don't take this lock, so go ahead and abuse it */
|
|
GST_LOCK (bus);
|
|
|
|
if (bus->num_signal_watchers == 0)
|
|
goto error;
|
|
|
|
bus->num_signal_watchers--;
|
|
|
|
if (bus->num_signal_watchers > 0)
|
|
goto done;
|
|
|
|
g_source_remove (bus->signal_watch_id);
|
|
bus->signal_watch_id = 0;
|
|
|
|
done:
|
|
GST_UNLOCK (bus);
|
|
return;
|
|
|
|
error:
|
|
{
|
|
g_critical ("Bus %s has no signal watches attached", GST_OBJECT_NAME (bus));
|
|
GST_UNLOCK (bus);
|
|
return;
|
|
}
|
|
}
|